Treatment of Oligozoospermia by Tamoxifen: No Evidence for Direct Testicular Action

Abstract

The improvement of impaired spermatogenesis by tamoxifen is well documented. The antiestrogen seems to act via an enhancement of gonadotropin release from the hypothesis, but there is evidence for a direct testicular effect. The serum levels of gonadotropins and steroid hormones were studied in 22 patients with idiopathic oligozoospermia. To study the direct testicular effect, the response of 5 normal males to hCG [human chorionic gonadotropin] prior to and after the applicatin of tamoxifen was tested. FSH levels showed a continuous increase in the patients during the 3 mo. of treatment, while the stimulation by LHRH was not altered. In the case of LH [luteinizing hormone] the basal as well as the stimulated levels increased. Mean levels of testosterone, 17-hydroxyprogesterone, androstenedione and estradiol increased significantly during treatment. Sperm counts of patients were found to be considerably higher after 3 mo. In the normal males no differences in steroid levels as a response to hCG with and without tamoxifen treatment occurred. Apparently, the hormonal changes occurring under tamoxifen treatment are not due to a direct testicular effect.